Until fairly recently, the cable network was predominantly a vehicle for delivering entertainment. With the advent of the Internet and the rise in demand for broadband two-way access, the cable industry began to seek new ways of utilizing its existing plant. Pure coaxial (“coax”) cable networks were replaced with hybrid fiber networks (HFNs) using optical fiber from the head end to the demarcation with the subscriber coax (usually at a fiber node). Currently, a content-based network, a non-limiting example of which is a cable television network, may afford access to a variety of services besides television, for example, broadband Internet access, telephone service, and the like.
Designed for one-way delivery of broadcast signals, the existing cable network topology was optimized for downstream (toward the subscriber) only service. New equipment had to be added to the network to provide two-way communication. To reduce the cost of this equipment and to simplify the upgrade of the broadcast cable for two-way digital traffic, standards were developed for a variety of new cable-based services. The first of these standards, the Data Over Cable System Interface Standard (DOCSIS® standard), was released in 1998. DOCSIS® establishes standards for cable modems and supporting equipment. DOCSIS® (Data Over Cable Service Interface Specification) is a registered mark of Cable Television Laboratories, Inc., 400 Centennial Parkway Louisville Colo. 80027, USA, and will be referred to for the remainder of this application in capital letters, without the symbol, for convenience.
Furthermore, Internet access may be provided by many different kinds of networks, in addition to cable or other content-based networks.
One aspect of a communications network is provision of a notification mechanism. Various solutions exist today for notification mechanisms: (1) true messaging, e.g. Java Message Service (JMS)-based; (2) polling; and (3) COMET-based solutions, including long polling and web sockets. The skilled artisan will appreciate that COMET refers to a web application model in which a long-held HTTP request allows a web server to push data to a browser, without the browser explicitly requesting it.
An Internet-scoped web context is one instance in which a notification message may be desired. In such a context, very little infrastructure is typically deployed in the homes of users—basically, just a browser is typically present.